To produce primary titanium at a lower cost a most innovative electrolytic cell has been designed, based on over 30 years of development work on the electrolysis of titanium, and it is being tested. The cell works at high temperature, has a fluoride electrolyte and titanium metal is reduced in the liquid form with all the electrochemical benefits of a liquid cathode, as for example constant electrode area and constant anode-cathode distance. Under the operational conditions there are no intermediate valence titanium ions in the electrolyte, therefore no need for diaphragms which limit the cell productivity. The cell is fed with titanium tetrachloride and the dry chlorine gas produced is used in the integrated carbochlorination of titanium oxide raw material purification process, which in turn produces pure titanium tetrachloride feed for the titanium cell. The fluoride electrowinning cell has many of the industrial advantages of the aluminium cell, plus other favourable characteristics specific of the titanium system, as for example larger difference in density between liquid titanium and the electrolyte, higher melting point for the metal than for the electrolyte. The solidified cathode slab obtained with the fluoride cell is suitable for direct rolling, with large savings in scrap generation, manufacturing costs and avoiding operations where LDI or HDI are introduced into the metal. In synthesis, one electrolytic pot room replaces the several different plants used for current sponge production.
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